Frozen hamburgers, chicken patties, and other disc-like food products typically are prepared by a manufacturer on one piece of equipment, and then manually loaded into boxes or similar packaging with a separate packaging machine. Manufacturers of hamburger patties will form patties with a production machine. After being formed, they are fed into a freezer. After leaving the freezer, they are screened by a metal detector which ejects contaminated patties. The patties are then typically conveyed to a stacking machine. The frozen patties are manually placed into boxes. The number of patties in the boxes will vary, based upon size of the patties and the efficiency of the stacker.
Prior stacking machines typically form a large number of lanes of food product, generally more lanes than the number of stacks that will fit in the box. It is difficult to form stacks for each lane, and then form a pattern of stacks which will fit in each case.
Changing the dimensions of the box or carton negatively effects the length to width ratios of the box, resulting in receptacles which are awkward and imbalanced. Moreover, the patties may be of varying size, so the stacking machines have a difficult time accommodating product of varying sizes. Thus, there is a need in the art for a lane combining conveyor system which reduces the number of lanes of food product to the number of stacks required to fit lengthwise in a case.
Coil-type stackers are sometimes placed at a drop off from the conveyor system so that product will be dropped and stacked between the turns of the coils. When the patties are randomly dropped onto the side of the coil, a patty may occasionally contact the edge of the coil, causing the patty to be improperly positioned in the stack. Even coil stackers, however, require an operator to remove the products, and place them into the box. Improperly positioned product causes inconsistent forming of the stack of patties. This inconsistency makes it impossible to automate the transferring of the stacks of patties.
The common industry practice for loading patties into a case is to load them manually, after the food products are formed into continuous stacks by a coil type stacker. The operator will then pick up partial stacks of about 5-10 patties, and place them into the case. Robots have been used to place the patties into the box or carton, but robots are expensive and may have difficulty should product size change.
The disclosed invention achieves these needs and others by providing a lane combining conveyor, used in connection with a stack former, a stack transfer mechanism, a matrix former, and a case rollover mechanism. The disclosed invention automatically sorts the patties into a number of lanes corresponding to the number of stacks in the carton, assembles them into stacks of predetermined number of patties, and then causes the stacks to be positioned within a carton. The invention operates essentially automatically, can be adjusted as to the number of stacks and the number of patties in a stack, and avoids the need for an operator to manually place the stacks into a carton.